Titaniferous biotite lubricant



United States Patent Int. Cl. C10m /02 US. Cl. 252-28 9 Claims ABSTRACTOF THE DISCLOSURE A method for converting titaniferous biotite ore intoa lubricating composition by grinding the ore into small particles,expanding the particles by heating to 1000 to 1400 F., cooling theparticles, treating the particles with nitric acid at least 5 N, washingthe ore particles with an alkaline solution, and heating the particlesbelow 1400 F. until dry. In preferred embodiments, a second acidtreatment with phosphoric acid at least 1 N is used after nitric acidtreatment; the alkaline solution is a sodium hydroxide solution; the oreis ground to 0.5 to 400 microns; and the expansion and drying steps arecarried out below 1250 F.

This invention relates to a method of making lubricating compositions.

The object of this invention is to provide a simple and economicalmethod for preparing an effective, low-cost, solid, particulatelubricating composition from raw titaniferous biotite ore, a relativelyrare boitite ore which is unusually rich in titanium and aluminum.

The invention features converting titaniferous biotite ore, having atotal silicon, potassium and magnesium content of at least 50% byweight, a total sodium, iron and phosphorus content of at least but lessthan 50% by Weight, a total manganese, aluminum, strontium, titanium,copper and calcium content of at least 1% but less than 10% by weight,and less than a total 1% by weight of trace elements including nickel,to a lubricating composition by grinding the ore into particles of apreselected size, heating the ore particles to 1000 to 1400 F. to expandthe particles, cooling the particles, treating the ore particles with anacid solution comprising nitric acid at least 5 N, washing the oreparticles with an alkaline solution, and heating the ore particles at atemperature below 1400 F. until dry. In preferred embodiments, the oreparticles are treated with a second acid solution comprising at least 1N phosphoric acid following the nitric acid treatment and before thealkaline washing; the acid solutions are 5 to 7 N nitric acid and 1 to 3N phosphoric acid; the alkaline solution is dilute (e.g., 0.2 N) sodiumhydroxide; the heating and drying are both carried out below 1250 F.;the acid treatment is carried out at about 100 F.; the ore particles arewashed, after nitric acid and alkali treatment, with softened water; andthe ore is ground to particle sizes ranging from 0.5 to at least about400 microns.

Other objects, features and advantages will appear from the followingdescription.

The initial heating (which expands or exfoliates the ore) and the finaldrying should be carried out at temperatures high enough to effectexpansion or drying, but below the roasting or scorching temperature ofthe ore (usually above 1400 F.). Where temperatures near this upperlimit are used, the heating should not be carried on for an excessivelylong period (e.g., not more than minutes at 1400 F.). The nitric acidused should preferably be about 5 to 7 N for the most efiicient removalof constituents undesirable in lubricating compositions, such as ironand lead salts, as well as dirt and other unwanted materials. Althoughit is possible to produce an Patented Sept. 29, 1970 'ice effectiveadditive by using only nitric acid, an improved product results if thesecond phosphoric acid treatment is also used. About 1 to 3 N phosphoricacid is preferred. About A pint acid to one pound ore is presentlypreferred. Sodium hydroxide is one example of a strong base which may beused for the purposes of neutralizing acid left in the ore sample afteraqueous washings but the others may also be used. A 0.2 N solution ispresently preferred to effectively neutalize the unwanted remaining acidwith- .out introducing an equally undesirable alkalinity into the ore.

The size to which the ore is initially ground, as well as the amounts ofore to be added to lubricants such as greases, depends on the use to bemade of the particulate ore composition or of the overall lubricatingmixture. In general, the particulate ore composition of the presentinvention may be used in sizes and amounts comparable to those in whichother solid lubricating compositions, such as molybdenum disulfide, areused; preferred particle sizes range from about 0.25 to 400 microns, andpreferred amounts range from 0.1 to 70% by total weight of lubricatingcomposition. Among the additive uses for which the particulate orecomposition of the present invention is particularly effective are: gearand bearing greases (especially, oscillating bearing lubrication),dryfilm lubrication, for incorporation into plastic parts which requirelubrication, and wherever high temperature greases are required; alone,the composition may be used, e.g., as a sealed lubricant for sealedbearings.

EXAMPLE Titaniferous biotite ore was ground to particule sizes of about200 to 400 microns. The ore particles were heated at 1200 F. for 15minutes. After cooling to room temperature, the ore particles weremixed, with agitation, for one hour with about A pint, per pound of ore,of 6 N nitric acid, at F. The particles were then filtered, Washed at100 F. for one hour with softened water (the same orezliquid ratio beingobserved as with the nitric acid), and filtered again. The particleswere then similarly mixed with 2 N phosphoric acid, the same amounts andreaction conditions being observed as in the nitric acid treatment.After filtering, washing with softened water, as above, and filteringagain, the ore particles were mixed with 0.2 N sodium hydroxide at 70 F.for one hour, the same particle:liquid ratio being observed. Theparticles were filtered, washed with softened water for /2 hour at 100F., and filtered again. Finally, the particles were heated in a furnaceat 1200 F. until dry.

The dried ore particles were then added, in amounts ranging from 4 to20% by total weight of mixture, to Arnolith Grease No. 2, a tradedesignation for a type of pure petroleum grease. It has been heretoforeknown that titaniferous biotite ore can be made into such an additive.The grease and greasezore mixtures were subjected to a series ofstandard wear and temperature tests. The grease: ore mixture was foundto have improved wear preventive characteristics over the grease alone,and also to be useful at significantly higher temperatures than the puregrease.

Other embodiments will occur to those skilled in the art and are Withinthe following claims.

What is claimed is:

1. A method for converting titaniferous biotite ore having a totalsilicon, potassium and magnesium content of at least 50% by weight, atotal sodium, iron and phosphorus content of at least 10% but less than50% by weight, a total manganese, aluminum, strontium, titanium, copperand calcium content of at least 1% but less than 10% by weight, and lessthan a total 1% by weight of trace elements including nickel, into alubricating composition, said method comprising the steps of grindingsaid ore into particles of a preselected size,

heating said ore particles to 1000 to 1400 F. to expand said particles,

cooling said particles,

treating said ore particles with an acid solution comprising at least 5N nitric acid,

washing said ore particles with an alkaline solution,

and

heating said ore particles at a temperature less than 1400 F. until dry.

2. The method of claim 1 wherein said first acid solution is a 5 to 7 Nsolution of nitric acid.

3. The method of claim 1 including the step of treating said oreparticles with a second acid solution comprising at least 1 N phosphoricacid following said nitric acid treatment and prior to said alkalinewashing.

4. The method of claim 3 wherein said second acid solution is a 1 to 3 Nsolution of phosphoric acid.

5. The method of claim 1 wherein said alkaline solution is a solution ofsodium hydroxide.

6. The metod of claim 1 wherein said ore particles are washed withsoftened water after said acid treatment and after said alkalinetreatment.

7. The method of claim 1 wherein said titaniferous biotite ore is groundto particles sized in the range of about 0.5 to 400 microns.

8. The method of claim 1 wherein each said heating is carried out at atemperature below 1250 F.

9. A method for converting raw titaniferous biotite ore having a totalsilicon, potassium and magnesium content of at least 50% by weight, atotal sodium, iron and phosphorus content of at least 10% but less than50% by weight, a total manganese, aluminum, strontium, titanium, copperand calcium content of at least 1% but less than 10% by weight, and lessthan a total 1% by weight of trace elements including nickel, into alubricating composition, said method comprising the steps of grindingsaid ore into particles of preselected size, heating the ore particlesto 1200 F. for one hour, cooling the ore particles, mixing said oreparticles with 6 N nitric acid and maintaining said mixture at 100 F.for about one hour while agitating said mixture, washing said oreparticles with softened water to remove said nitric acid, mixing saidore particles with 2 N phosphoric acid and maintaining said mixture at100 F. for one hour while agitating said mixture, washing said oreparticles with 0.2 N sodium hydroxide at room temperature for one halthour to neutralize remaining acids, washing said ore particles withsoftened water, and heating said particles at a temperature below 1250F. until dry.

References Cited UNITED STATES PATENTS 11/1963 Gordon 252-28 4/ 1965Slater et a1. 252-28 U.S. Cl. X.R. 252-378

